Devices for material delivery, electroporation, sonoporation, and/or monitoring electrophysiological activity

ABSTRACT

The invention relates generally to systems and devices for material delivery, energy delivery, and/or monitoring electrophysiological activity, and method of use thereof. In particular, the present invention provides devices and systems, and methods of use thereof, configured to deliver therapeutic compositions, to provide electroporation and/or sonoporation to increase therapeutic efficiency, and to monitor electrophysiological activity, for example, before and after treatment.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 13/080,755, filed Apr. 6, 2011, which is a continuation-in-partof U.S. patent application Ser. No. 12/959,864, filed Dec. 3, 2010, nowabandoned, which claims priority to U.S. Provisional Application61/266,280, filed Dec. 3, 2009, each of which is herein incorporated byreference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with government support under Grant No. K08HL074192 awarded by the National Institutes of Health, the NationalHeart, Lung, and Blood Institute. The government has certain rights inthe invention.

FIELD OF THE INVENTION

The invention relates generally to systems and devices for materialdelivery, energy delivery, and/or monitoring electrophysiologicalactivity, and method of use thereof. In particular, the presentinvention provides devices and systems, and methods of use thereof,configured to deliver therapeutic compositions, to provideelectroporation and/or sonoporation to increase therapeutic efficiency,and to monitor electrophysiological activity, for example, before andafter treatment.

BACKGROUND OF THE INVENTION

Gene-based approaches have been used to treat or palliate a variety ofdisease processes. For example, attempts have been made to use agene-based approach to target rhythm disorders of the heart (e.g. atrialfibrillation) (AF) (Arora et al. Heart Rhythm. 2008; 5(5S):S55., hereinincorporated by reference in its entirety). However, targeting a gene‘cargo’ to an organ of interest presents a variety of challenges. (Deanet al. Am J Physiol Cell Physiol. August 2005; 289(2):C233-245., Dean etal. Gene therapy. September 2003; 1 0(18): 1608-1615., Donahue. Journalof cardiovascular electrophysiology. May 2007; 18(5):553-559, hereinincorporated by reference in their entireties) Systemic gene deliveryoften results in sub-therapeutic concentrations of a gene in the organof interest. In addition, systemic delivery carries the risk ofunwarranted gene expression in organs that are remote from the region ofinterest, with the potential for significant side effects.

Catheter systems for local delivery of therapeutic agents have manyadvantages. Approaches for local delivery of agents at a depth within atissue are applicable to the heart, pancreas, esophagus, stomach, colon,large intestine, and other tissues which may be accessed via a cathetersystem. These catheter systems will deliver drugs to the sites wherethey are most needed, reduce the amount of drug required, increase thetherapeutic index, and control the time course of agent delivery. These,in turn, improve the viability of the drugs, lower the amount (and cost)of agents, reduce systemic effects, reduce the chance of drug-druginteractions, lower the risk to patients, and allow the physician tomore precisely control the effects induced. Such local delivery maymimic endogenous modes of release, and address the issues of agenttoxicity and short half lives.

AF is the most common sustained arrhythmia disturbance, occurring in0.4% of the general population and in up to 40% of patients withcongestive heart failure (CHF). It is a cause of significant morbidity(such as cerebrovascular embolism or ‘stroke’) and also contributes toincreased mortality (Balasubramaniam & Kistler. Heart (British CardiacSociety). Jul. 16, 2008., herein incorporated by reference in itsentirety). The diagnosis and management of AF have therefore become animportant and challenging aspect of cardiovascular medicine.Unfortunately, current approaches to cure this arrhythmia are inadequate(Gerstenfeld et al. Heart Rhythm. February 2006; 3(2): 165-170., hereinincorporated by reference in its entirety). The posterior left atrium(PLA) has been shown to play a significant role in the genesis of AF(Haissaguerre et al. Circulation. Mar. 28, 2000; 1 01 (12): 1409-1417.,Haissaguerre et al. The New England Journal of Medicine. Sep. 3, 1998;339(10):659-666, herein incorporated by reference in their entireties).This region has been shown to possess unique structural andelectrophysiological characteristics that appear to contribute tosubstrate for AF. Both sympathetic and parasympathetic activity in theheart is mediated by heterotrimeric G-protein (GαGα3Gα) coupled pathwaysinitiated by G-protein coupled receptors (GPCRs). A gene-based approachcan be used to selectively inhibit the G-protein signaling pathways thatare critical to autonomic signaling in the atrium (Arora et al. HeartRhythm. 2007; 4(5S):S9., Arora et al. Heart Rhythm. 2008; 5(5S):S55.,herein incorporated by reference in their entireties).

SUMMARY OF THE INVENTION

In some embodiments, the present invention provides a device comprising:(a) an elongate member with an inner lumen configured for delivery of atherapeutic agent to a treatment site within a subject, (b) anenergy-delivery element configured to deliver energy to the treatmentsite within a subject, and (c) an electrophysiology monitoring elementconfigured to monitor electrical signals (e.g. at or around thetreatment site within said subject, such as the heart (e.g., epicardium,endocardium, etc.) or other organs, organ systems, and body systems. Insome embodiments, an energy-delivery element is an electroporationelement and/or a sonoporation element. In some embodiments, the presentinvention provides a device comprising: (a) an elongate member with aninner lumen configured for delivery of a therapeutic agent to atreatment site within a subject, and (b) an energy-delivery element(e.g., an electroporation element, a sonoporation element, etc.)configured to deliver energy (e.g., electric current, sound waves,ultrasonic energy, etc.) to the treatment site within a subject. In someembodiments, the present invention provides a device comprising: (a) anelongate member with an inner lumen configured for delivery of atherapeutic agent to a treatment site within a subject, and (b) anelectrophysiology monitoring element configured to monitor and/or recordelectrical signals. In some embodiments, the present invention providesa device comprising: (a) an electrophysiology monitoring elementconfigured to monitor electrical signals and (b) an energy-deliveryelement (e.g., an electroporation element, a sonoporation element, etc.)configured to deliver energy (e.g., electric current, sound waves,ultrasonic energy, etc.) to the treatment site within a subject. In someembodiments, the energy-delivery element (e.g., an electroporationelement, a sonoporation element, etc.) is located at the distal tip ofthe device (e.g., at or near the distal end of the elongate member). Insome embodiments, the energy-delivery element (e.g., an electroporationelement, a sonoporation element, etc.) comprises one or moreelectroporation electrodes (e.g., which may be at or near the end of theelongate member). In some embodiments, the energy-delivery element(e.g., an electroporation element, a sonoporation element, etc.)comprises a plurality of electroporation electrodes (e.g., which may beat or near the end of the elongate member). In some embodiments, theenergy-delivery element (e.g., an electroporation element, asonoporation element, etc.) comprises one or more sonoporation elements,sonoporators, ultrasound generators, piezoelectric transducers (e.g.,which may be at or near the end of the elongate member). In someembodiments, the electrophysiology monitoring element comprises aplurality of recording electrodes. In some embodiments, the plurality ofmonitoring electrodes comprises one or more distal monitoring electrodesand one or more proximal monitoring electrodes. In some embodiments, thedevice further comprises a handle located at the proximal end of thedevice. In some embodiments, the handle comprises one or more controlelements. In some embodiments, the handle comprises one or moreinjection ports in fluid communication with the inner lumen. In someembodiments, the injection ports are configured for the loadingtherapeutic agents into the inner lumen. In some embodiments, a devicecomprises an inflatable and deflatable balloon element located at thedistal tip of the elongate member. In some embodiments, theenergy-delivery element (e.g., an electroporation element, asonoporation element, etc.) is located on the balloon element. In someembodiments, the energy-delivery element (e.g., an electroporationelement, a sonoporation element, etc.) comprises piezoelectric crystalsconfigured to generate ultrasound energy. In some embodiments, theenergy-delivery element (e.g., an electroporation element, asonoporation element, etc.) comprises electrodes mounted and/or housedin and/or on the balloon element. In some embodiments, theelectrophysiology monitoring element is located in and/or on saidballoon element.

In some embodiments, the present invention provides a device comprising:(a) an elongate member configured for providing access to a treatmentsite within a subject, (b) an energy-delivery element configured todeliver energy to the treatment site within a subject, and (c) anelectrophysiology monitoring element configured to monitor electricalsignals (e.g. at or around the treatment site within said subject, suchas the heart (e.g., epicardium, endocardium, etc.) or other organs,organ systems, and body systems. In some embodiments, an energy-deliveryelement is an electroporation element and/or a sonoporation element. Insome embodiments, the elongate member comprises an inner lumen (e.g.,for materials delivery). In some embodiments, the present inventionprovides a device comprising: (a) an elongate member configured forproviding access to a treatment site within a subject, and (b) anenergy-delivery element configured to deliver energy to the treatmentsite within a subject. In some embodiments, the present inventionprovides a device comprising: (a) an elongate member configured forproviding access to a treatment site within a subject, and (b) anelectrophysiology monitoring element configured to monitor electricalsignals (e.g. at or around the treatment site within said subject, suchas the heart (e.g., epicardium, endocardium, etc.) or other organs,organ systems, and body systems.

In some embodiments, the present invention provides a systemcomprising 1) a material delivery device, wherein said device comprisesan elongate structure configured to access a treatment site within asubject and deliver physical material (e.g., therapeutic agent (e.g.,nucleic acid)) to that site; and 2) an energy deliver/monitoring devicecomprising (a) an elongate member configured for providing access to atreatment site within a subject, (b) an energy-delivery elementconfigured to deliver energy to the treatment site within a subject, and(c) an electrophysiology monitoring element configured to monitorelectrical signals (e.g. at or around the treatment site within saidsubject, such as the heart (e.g., epicardium, endocardium, etc.) orother organs, organ systems, and body systems. In some embodiments, amaterial delivery device comprises an inner lumen through which material(e.g., therapeutic agent (e.g., nucleic acid)) can pass. In someembodiments, a material delivery device comprises a catheter. In someembodiments, the present invention provides methods for treating asubject wherein (a) a material delivery device is used to delivertherapeutic material (e.g., nucleic acids) to a treatment site (e.g. theheart or other organ systems); and (b) an energy deliver/monitoringdevice delivers energy (e.g., electric, ultrasound, etc.) to thetreatment site to enhance the therapeutic effect of the therapeuticmaterial. In some embodiments, a first device provides delivery of atherapeutic agent to a site within a subject (e.g., heart (e.g.,epicardium, endocardium) or other tissue or organ system) and a seconddevice provides sonoporation or electroporation to enhance thetherapeutic effect of the therapeutic agent.

In some embodiments, the present invention provides a method of treatinga disease or condition in a subject comprising: (a) inserting a catheterinto the subject and placing the distal end of the catheter at or near atreatment site, (b) delivering a therapeutic agent to the treatment sitethrough the lumen of the catheter, and (c) electroporating and/orsonoporating the treatment site with energy-delivery elements (e.g., anelectroporation element, a sonoporation element, etc.) located on thedistal end of the catheter (e.g., such that cells at the treatment siteare transfected with reagents delivered via the catheter). In someembodiments, a treatment site is electroporated but not sonoporated. Insome embodiments, a treatment site is sonoporated but notelectroporated. In some embodiments, a treatment site is electroporatedand sonoporated. In some embodiments, the method further comprises aninitial step of monitoring electrical signals at the treatment site withan electrophysiology monitoring element. In some embodiments, the methodfurther comprises (d) monitoring electrical signals at the treatmentsite with an electrophysiology monitoring element. In some embodiments,the method further comprises (e) comparing electrical signals from theinitial step with electrical signals of step (d). In some embodiments,the method further comprises (f) determining the effectiveness of thetreating based on comparison of the electrical signals from the initialstep with electrical signals of step (d). In some embodiments, thetherapeutic agent comprises gene therapy reagents. In some embodiments,the gene therapy reagents comprise nucleic acids (e.g., plasmids or AAVvectors comprising a gene of interest). In some embodiments, the nucleicacids comprise DNA. In some embodiments, the DNA comprises one or moremini-genes.

In some embodiments, the present invention provides a method of treatinga disease or condition in a subject comprising: (a) delivering atherapeutic agent to s treatment site within a subject (e.g., cardiactissue (e.g., epicardium, endocardium) or other non-cardiac tissues andbody systems), and (b) electroporating and/or sonoporating the treatmentsite with an energy-delivery element (e.g., an electroporation element,a sonoporation element, etc.) such that cells at the treatment site aretransfected with the thereapeutic agents. In some embodiments, thetherapeutic agent and electroporation/sonoporation energy are deliveredto the treatment site through a single device. In some embodiments, thetherapeutic agent and electroporation/sonoporation energy are deliveredto the treatment site through separate devices. In some embodiments, thepresent invention provides a method of treating a disease or conditionin a subject comprising: (a) delivering a therapeutic agent to streatment site within a subject (e.g., cardiac tissue (e.g., epicardium,endocardium) or other non-cardiac tissues and body systems), (b)electroporating and/or sonoporating the treatment site with anenergy-delivery element (e.g., an electroporation element, asonoporation element, etc.) such that cells at the treatment site aretransfected with the thereapeutic agents, and (c) monitoring theelectrophysiological activity at the treatment site (e.g., before and/orafter treatment).

In some embodiments, the present invention comprises a systemcomprising: (a) an elongate member comprising an inner lumen, whereinsaid inner lumen is configured for delivery of a therapeutic agent to atreatment site within a subject, (b) an energy-delivery element (e.g.,an electroporation element, a sonoporation element, etc.), wherein saidenergy-delivery element (e.g., an electroporation element, asonoporation element, etc.) is configured to deliver energy (e.g.,electric current, ultrasonic energy) to said treatment site within asubject, and (c) an electrophysiology monitoring element, wherein saidelectrophysiology monitoring element is configured to monitor electricalsignals (e.g., in an around the treatment site in order to guide thedevice). In some embodiments, a system provides an elongate member withan inner lumen and energy-delivery element (e.g., an electroporationelement, a sonoporation element, etc.) element. In some embodiments, asystem comprises an elongate member with an inner lumen and anelectrophysiology monitoring element. In some embodiments, a systemcomprises an energy-delivery element (e.g., an electroporation element,a sonoporation element, etc.) and an electrophysiology monitoringelement. In some embodiments, the energy-delivery element (e.g., anelectroporation element, a sonoporation element, etc.) is located at thedistal tip of the system. In some embodiments, the energy-deliveryelement (e.g., an electroporation element, a sonoporation element, etc.)comprises a plurality of electroporation electrodes. In someembodiments, the electrophysiology recording element comprises aplurality of monitoring electrodes. In some embodiments, the pluralityof monitoring electrodes comprises one or more distal monitoringelectrodes and one or more proximal monitoring electrodes. In someembodiments, the system further comprises a handle located at theproximal end of the system. In some embodiments, the handle comprisesone or more control elements. In some embodiments, the handle comprisesone or more injection ports in fluid communication with the inner lumen.In some embodiments, the injection ports are configured for loadingtherapeutic agents into the inner lumen.

BRIEF DESCRIPTION OF THE DRAWINGS

The description provided herein is better understood when read inconjunction with the accompanying drawings which are included by way ofexample and not by way of limitation.

FIG. 1 shows exemplary electroporation electrodes.

FIG. 2A shows the results of PCR on PLA tissue injected with exemplarygene therapy minigene.

FIG. 2B shows the results of RT-PCR demonstrating the expression of aninjected miniene in the PLA, but not the LAA.

FIG. 3 shows an exemplary Western blot for a FLAG-tagged Gαi peptide.

FIG. 4 shows exemplary results of immunostaining for FLAG-tagged Gαi1/2peptide.

FIG. 5 shows exemplary effects of Gαi1/2 minigene on vagal-induced ERPshortening.

FIG. 6 shows a graph depicting VS-induced ERP shortening in caninesubjects receiving Gαi1/2 and GαR (random) minigenes.

FIG. 7 shows diminishment of vagal-induced AF-inducibility followingGαi1/2 minigene injection.

FIG. 8 shows a graph depicting no change in vagal-inducedAF-inducibility following GαR minigene injection.

FIG. 9A an exemplary catheter device of the present invention.

FIG. 9B shows an exemplary distal end of a catheter shaft of the presentinvention.

FIG. 10 shows an exemplary catheter and electroporation balloon of thepresent invention.

FIG. 11 shows an exemplary catheter and ultrasound balloon of thepresent invention.

FIG. 12 shows a side view of an exemplary energy-delivery element.Recording electrodes and electroporation- and/or sonoporation-emittingelements are positioned along an energy-delivery element, e.g., tofacilitate placement against a body tissue (e.g., epicardium, othercardiac surface, and/or other non-cardiac surface).

FIG. 13 shows a side view of an exemplary energy-delivery element.Recording electrodes and electroporation- and/or sonoporation-emittingelements are positioned along an energy-delivery element, e.g., tofacilitate placement against a body tissue (e.g., epicardium, othercardiac surface, and/or other non-cardiac surface).

DEFINITIONS

As used herein, the term “subject” refers to any animal including, butnot limited to, insects, humans, non-human primates, vertebrates,bovines, equines, felines, canines, pigs, rodents, and the like. Theterms “subject” and “patient” may be used interchangeably, wherein theterm “patient” generally refers to a subject seeking or receivingtreatment or preventative measures from a clinician or health careprovider. A subject may be of any stage of life (e.g. embryo, fetus,infant, neonatal, child, adult, live, dead, etc.).

As used herein, the term “effective amount” refers to the amount of acompound sufficient to effect beneficial or desired results. Aneffective amount can be administered in one or more administrations,applications or dosages and is not limited to or intended to be limitedto a particular formulation or administration route.

As used herein, the term “pharmaceutical composition” refers to thecombination of an active agent with a carrier, inert or active, makingthe composition especially suitable for diagnostic or therapeutic use invivo, in vivo or ex vivo.

The term “gene therapy” is given its ordinary meaning in the art.Briefly, “gene therapy” refers to the transfer of genetic material(e.g., a DNA or RNA polynucleotide) of interest into a host cell and/ortissue to treat or prevent a disease condition. The genetic material ofinterest typically encodes a product whose in vivo production isdesired. The genetic material of interest can also include variouscontrol elements, such as transcriptional promoters. It is noted thatthe end result of gene therapy does not have to always include a cure,but instead, also includes reducing the severity of one or more symptomsof a disease.

DETAILED DESCRIPTION

In some embodiments, the present invention provides catheter devices. Insome embodiments, catheter devices are configured for material delivery,energy delivery (e.g. electroporation, ultrasound energy), and/ormonitoring electrophysiological activity. In some embodiments, cathetersare configured to deliver materials to a specific location within asubject (e.g. organ, portion of an organ, heart, artery, tissue, etc.).In some embodiments, catheters are configured to provide energy deliveryenergy (e.g., electric energy, ultrasonic energy, etc.),electroporation, or sonoporation (e.g., to facilitate or increase theefficiency of therapeutic uptake into cells). In some embodiments,catheters are configured to provide electric energy (e.g. to facilitateor increase the efficiency of therapeutic uptake into cells). In someembodiments, catheters are configured to provide ultrasound energy (e.g.to facilitate or increase the efficiency of therapeutic uptake intocells). In some embodiments, the present invention is configured tomonitor physiological electric signals or impulses. In some embodiments,the present invention is configured to record intracardiacelectrophysiologic activity (e.g. electrocardiogram). In someembodiments, a single catheter is configured to perform two or morefunctions of the present invention, e.g., therapeutic-agent delivery,energy delivery (e.g., sonoporation, electroporation, etc.), accessing atreatment site within a subject, electrophysiological monitoring, etc.In some embodiments, a system of the present invention comprises two ormore devices configured to perform two or more functions of the presentinvention, e.g., therapeutic-agent delivery, energy delivery (e.g.,sonoporation, electroporation, etc.), accessing a treatment site withina subject, electrophysiological monitoring, etc. In some embodiments,the present invention provides a device or system comprising (a) theability to record and/or monitor electrical signals (e.g. in order toguide or determine the effectiveness of gene injection, electroporation,and/or ultrasound), (b) the ability to deliver a biologically active‘cargo’ (e.g. naked DNA) (e.g. via a transvenous (transseptal)approach), and (c) the ability to perform electroporation and/orapplication of ultrasound energy (e.g. to facilitate intracellular genetransfer). In some embodiments, the present invention provides a systemcomprising a catheter with a lumen, energy-delivery element (e.g.,electroporation element, sonoporation element, etc.), and anelectrophysiology monitoring element.

In some embodiments, the present invention provides devices, systems,and methods to direct electroporation to target delivery sites within asubject. Electroporation, or electropermeabilization, is a significantincrease in the electrical conductivity and permeability of the cellplasma membrane caused by an externally applied electrical field. Insome embodiments, a device of the present invention directs an appliedelectric field toward a treatment site to aid in therapeutic (e.g.,nucleic acid) uptake. In some embodiments, a device of the presentinvention directs an applied electric field toward a treatment site todestroy tissue and/or cells at the treatment site. In some embodiments,any suitable level of electric current can be delivered through a deviceof the present invention and applied to a site within a subject. In someembodiments, the level of electric current applied to a site (e.g.treatment site, delivery site, etc.) is selected based on theapplication (e.g., enhancement of therapeutic delivery, tissue ablation,etc.), subject (e.g., species, size, age, etc.), treatment site (e.g.,epicardium, endocardium, non-cardiac tissue, etc.), and considerationsknown to those of skill in the art. In some embodiments, electriccurrent is delivered continuously for a period of time (e.g., 1 second .. . 2 seconds . . . 5 seconds . . . 10 seconds . . . 30 seconds . . . 1minute . . . 2 minutes . . . 5 minutes . . . 10 minutes . . . 30 minutes. . . 1 hour, or more). In some embodiments, electric current is pulsed.In some embodiments, the length of pulse, current applied, and durationof pulsing are selected based on appropriate criteria determined by askilled artisan or clinician. In some embodiments, the level of electriccurrent applied by a device of the present invention is between 0.01 Ampand 100 Amp (e.g., 0.01 Amp . . . 0.02 Amp . . . 0.05 Amp . . . 0.1 Amp. . . 0.2 Amp . . . 0.5 Amp . . . 1.0 Amp . . . 2.0 Amp . . . 5.0 Amp .. . 10 Amp . . . 20 Amp . . . 50 Amp . . . 100 Amp). In someembodiments, pulses are 0.1 seconds to 10 seconds in length (e.g., 0.1 s. . . 0.2 s . . . 0.5 s . . . 1 s . . . 2 s . . . 5 s . . . 10 s), anddelivered for 1 s to 1 hour (e.g., 1 second . . . 2 seconds . . . 5seconds . . . 30 seconds . . . 1 minute . . . 2 minutes . . . 5 minutes. . . 10 minutes . . . 30 minutes . . . 1 hour).

In some embodiments, the present invention provides devices, systems,and methods to direct sonoporation to target delivery sites within asubject. Sonoporation, or cellular sonication, is the use of sound(e.g., ultrasonic frequencies) for modifying the permeability of thecell plasma membrane. In some embodiments, a device of the presentinvention directs sonic energy (e.g., ultrasound frequencies) to atreatment site to aid in therapeutic (e.g., nucleic acid) uptake. Insome embodiments, a device of the present invention directs anultrasound (e.g., cyclic sound pressure) toward a treatment site todestroy tissue and/or cells at the treatment site. In some embodiments,any suitable level of ultrasound can be delivered through a device ofthe present invention and applied to a site within a subject. In someembodiments, the level and/or frequency of ultrasound applied to a site(e.g. treatment site, delivery site, etc.) is selected based on theapplication (e.g., enhancement of therapeutic delivery, tissue ablation,etc.), subject (e.g., species, size, age, etc.), treatment site (e.g.,epicardium, endocardium, non-cardiac tissue, etc.), and considerationsknown to those of skill in the art. In some embodiments, ultrasound isdelivered continuously for a period of time (e.g., 1 second . . . 2seconds . . . 5 seconds . . . 10 seconds . . . 30 seconds . . . 1 minute. . . 2 minutes . . . 5 minutes . . . 10 minutes . . . 30 minutes . . .1 hour, or more). In some embodiments, ultrasound is pulsed. In someembodiments, the length of pulse, level and/or frequency of ultrasoundapplied, and duration of pulsing are selected based on appropriatecriteria determined by a skilled artisan or clinician. In someembodiments, the frequency of ultrasound applied by a device of thepresent invention is between 20 kHz and 200 MHz (e.g., 20 kHz . . . 50kHz . . . 100 kHz . . . 200 kHz . . . 500 kHz . . . 1 MHz . . . 2 MHz .. . 5 MHz . . . 10 MHz . . . 20 MHz . . . 50 MHz . . . 100 MHz . . . 200MHz). In some embodiments, the level of ultrasound applied by a deviceof the present invention has a mechanical index (MI) between 0.01 and 5(e.g., 0.01 . . . 0.02 . . . 0.05 . . . 0.1 . . . 0.2 . . . 0.5 . . .1.0 . . . 2.0 . . . 5.0). In some embodiments, pulses are 0.1 seconds to10 seconds in length (e.g., 0.1 s . . . 0.2 s . . . 0.5 s . . . 1 s . .. 2 s . . . 5 s . . . 10 s), and delivered for 1 s to 1 hour (e.g., 1second . . . 2 seconds . . . 5 seconds . . . 30 seconds . . . 1 minute .. . 2 minutes . . . 5 minutes . . . 10 minutes . . . 30 minutes . . . 1hour).

In some embodiments, an energy-delivery element is configured to emitenergy from the terminal portion of the distal tip, thereby directingenergy to a singular spot within the treatment site. In suchembodiments, the size and/or shape of the area targeted by the emittedenergy depends upon the size of the energy-delivery element, the shapeof the energy-delivery element, and the trajectory of the emittedenergy. In some embodiments, an energy-delivery element is configured toemit energy from a segment at or near the distal tip (e.g., thepenultimate segment) (SEE, e.g., FIGS. 12 and 13), thereby directingenergy to a region within the treatment site in contacted by theenergy-delivery segment. In such embodiments, the size and/or shape ofthe area targeted by the emitted energy depends upon the arrangement ofenergy-emitting elements on the energy-delivery segment and theorientation of the energy-delivery segment on the treatment site. Insome embodiments, an energy-delivery segment is a linear segment of anelongated device, wherein energy-delivery elements (e.g., sonoporationelements, electroporation elements, etc.) are arranged along the lengthof the segment. In some embodiments, electrophysiology monitoringelements are spaced along the same segment as the energy-deliveryelements. In some embodiments, the length of an energy-delivery segmentis positioned along the desired treatment site. In some embodiments, thelength of an energy-delivery segment is clamped around a desiredtreatment site. In some embodiments, a device of the present inventionis configured to position an energy-delivery element or energy-deliverysegment to direct energy to a desired position or region of thetreatment site. In some embodiments, one or more various positioning andstabilizing elements (e.g., clamp, balloon, clip, vacuum, etc.) areutilized to position an energy-delivery element or energy-deliverysegment in the proper position on or within a treatment site.

In some embodiments, the present invention comprises an elongate member(e.g. a material-delivery/energy-delivery/electrophysiology catheter).In some embodiments, an elongate member is a catheter or othersite-access element. In some embodiments, a catheter shaft is flexible(e.g., bendable). In some embodiments the catheter is flexiblethroughout its length. In some embodiments the catheter is flexible atits distal end. In some embodiments, the catheter is substantiallynon-compressible along its length. In some embodiments, the presentinvention comprises a delivery, electroporation, sonoporation (e.g.,ultrasound), and/or electrophysiology catheter. In some embodiments, theouter wall comprises an imbedded braided mesh of stainless steel or thelike, as is generally known in the art, to increase torsional stiffnessof the catheter shaft so that, when the proximal catheter end isrotated, the distal catheter shaft will rotate in a correspondingmanner. In some embodiments, torsional stiffness is achieved throughother mechanisms known to those in the art. In some embodiments, theuseful length of the catheter, e.g., that portion that can be insertedinto the body, varies as desired. In some embodiments, the useful lengthranges from about 30 cm to about 300 cm (e.g. 30 cm . . . 40 cm . . . 50cm . . . 100 cm . . . 200 cm . . . 300 cm). In some embodiments, thediameter, circumference, and/or gauge of the catheter varies as desired.In some embodiments, useful outer diameters range from about 3-36 French(Fr) (e.g., 3 Fr, 4 Fr, 5 Fr, 6 Fr, 7 Fr, 8 Fr, 9 Fr, 10 Fr, 11 Fr, 12Fr, 13 Fr, 14 Fr, 15 Fr, 16 Fr, 17 Fr, 18 Fr, 19 Fr, 20 Fr, 21 Fr, 22Fr, 23 Fr, 24 Fr, 25 Fr, 26 Fr, 27 Fr, 28 Fr, 29 Fr, 30 Fr, 31 Fr, 32Fr, 33 Fr, 34 Fr, 35 Fr, 36 Fr, or diameters therein). In someembodiments, catheter diameter varies throughout its length. In someembodiments, catheter diameter is constant throughout the length of theinsertion portion or catheter shaft. In some embodiments, the catheteris steerable to allow for navigation within a subject or workingenvironment (e.g. artery, vein, organ, etc.). In some embodiments, acatheter is steerable. In some embodiments, the catheter hasbidirectional steerablity (e.g. the distal end of the catheter isconfigured to be bendable in the left/right plane via controls at thecatheter handle), and/or rotational steerability (e.g. the distal end ofthe catheter is configured to have 360° bendability). One exemplarysteerable catheter is described in U.S. Pat. No. 5,656,029, hereinincorporated by reference in its entirety.

Optionally, a system may further include at least one visualizationmember for enhancing visualization of the treatment site (e.g., hearttissue). In some embodiments, for example, the visualization member mayinclude an optic imaging device, a thermal imaging device, an ultrasounddevice, an electrical imaging device, a Doppler imaging device or thelike, though any suitable device may be used.

Some embodiments of the invention also include at least one positioningdevice for contacting the treatment site (e.g., epicardium, endocardium,non-cardiac tissue, etc.) and positioning the device for treatment. Forexample, the positioning device may comprise a suction positioningdevice, positioning balloon, clamp, clip, etc.

In some embodiments, the energy-delivery element is coupled with atleast one guiding member such that a change in shape of the guidingmember causes a corresponding change in shape of the energy-deliveryelement. For example, the guiding member may comprise a deformablelinear member its shape being adjustable by a user, and wherein theenergy-delivery element comprises a deformable linear member (e.g.,energy-delivery segment) coaxially coupled with the guiding member so asto move with the guiding member. In some embodiments, the guiding memberis adjustable to at least partially encircle, abut, grasp, and/or sitadjacent to one or more selected tissues, organs, or portions thereof.In some embodiments, one or more clamps, balloons, and/or suctionelements assist in positioning, deforming, and/or shaping an energydelivery element to adopt a desired position on/in a treatment site.

Optionally, a system may further include at least one needle coupledwith the material-delivery element for insertion into the tissue (e.g.,epidardium) to enhance application of the at least one therapeuticagent. The material-delivery element itself may comprise at least oneneedle and at least one aperture adjacent a tip of each needle forallowing passage of the at least one therapeutic agent out of the needleto contact the treatment site (e.g., heart tissue). Optionally, theneedle may be retractable. For example, the retractable needle may beexposed and retracted via a pneumatic member coupled with thematerial-delivery element. In some embodiments, the retractable needleis exposed and retracted automatically when the material-deliveryelement the treatment site. In some embodiments, a depth of penetrationof the retractable needle into the heart tissue is adjustable. In someembodiments, a needle is used in conjunction with an energy-deliveryelement (e.g., sonoporation element, electroporation element, etc.) toenhance therapeutic delivery within tissue (e.g., cardiac tissue,non-cardiac tissue).

FIGS. 9A and 9B provide exemplary embodiments of the present invention.These embodiments should not be viewed as limiting the scope of thepresent invention. As shown in FIG. 9A, in some embodiments, the presentinvention comprises a handle portion and a shaft portion. The handleportion comprises an injection port, a means for holding the catheter byan operator, and controls for manipulating the catheter (e.g. thumbknob). The shaft portion, or shaft of the catheter, is the portion ofthe catheter which is inserted into, and maneuvered through a subject.The shaft may be of any suitable length and comprises a deflectable tip.In some embodiments, manipulation of the catheter handle by an operatorallows for placement of the catheter shaft and the catheter tip into anappropriate location within a subject for localized treatment. As shownin FIG. 9B, the catheter shaft and catheter tip comprise at least onecentral lumen. In some embodiments, the catheter may comprise aplurality of lumens. Generally, the lumen runs the length of thecatheter shaft and provides a means for delivering therapeutics to atreatment site. The lumen may also provide additional functions. In someembodiments, the distal tip and/or distal segment of the cathetercomprises a plurality of electrodes (e.g., for electroporation). In someembodiments, the distal tip and/or distal segment of the cathetercomprises one or more piezoelectric crystals or other ultrasoundproducing objects or devices (e.g., for sonoporation). In certainembodiments, the distal tip and/or distal segment of the cathetercomprises both one or more recording/monitoring electrodes formeasuring, monitoring and recoding electrophysiology signals, and one ormore electroporation electrodes for delivering electrical current. Insome embodiments, the distal tip and/or distal segment of the cathetercomprises one or more recording/monitoring electrodes for measuring,monitoring and recoding electrophysiology signals, and one or moresonoporation elements (e.g., ultrasound generator, piezoelectriccrystal, etc.) for delivering ultrasonic energy. In some embodiments,the distal tip and/or distal segment of the catheter comprises two typesof monitoring electrodes: distal monitoring electrodes which are locatedon the ultimate end of the tip, and one or more proximal monitoringelectrodes located at the catheter tip, but prior to the end. In someembodiments, electrodes are spaced around the distal tip and/or distalsegment of the catheter. In some embodiments, the distal tip and/ordistal segment of the catheter comprises elements for both sonoporationand electroporation. In some embodiments, the distal tip and/or distalsegment of the catheter comprises elements for: 1) recording/monitoringelectrophysiology, 2) sonoporation, and 3) electroporation.

In some embodiments, control of the catheter is provided by anintegrated hand-held control mechanism and/or handle mounted on theproximal end of the catheter. In some embodiments, the controlmechanism/handle can be of various types, and adapted for operating asteerable catheter wherein the bend of the catheter can be selectivelycontrolled by the operator. In some embodiments, controls are anintegral part of the handle portion of the catheter. In someembodiments, controls and/or steering mechanisms are part of a separateunit attached to, or operable connected to a catheter. In someembodiments, the mechanism/handle includes a set of controls, whichallow the operator to control the steering of the catheter and otheroperational functions of the catheter (e.g. materialinjection/deposition, electroporation, sonoporation, electrophysiologymeasurements, etc.). It will be apparent to one of ordinary skill in theart that other control mechanisms/handles can be employed with thesystems of the invention without departing from the scope thereof.Specifically, systems can include joystick controls for operating thesteerable catheters and can include controls for rotating the angle atwhich the distal end of the catheter bends. Other modifications andadditions can be made to the control mechanism/handle without departingfrom the scope of the invention. In some embodiments, the controlmechanism/handle controls therapeutic-delivery functionalities, steeringof the catheter, electrophysiology electrodes, electroporationelectrodes, sonoporation devices, an orientation/isolation balloon, andany other functions that are understood by one in the art.

In some embodiments, the present invention provides a cathetercomprising an inner lumen. In some embodiments, a catheter comprises oneor more inner lumens (e.g. 1, 2, 3, 4, 5, 6, 7, 8 inner lumens). In someembodiments, the inner lumen runs the length of the catheter shaft. Insome embodiments, the lumen is configured to contain one or moretherapeutic agents. In some embodiments, the lumen is configured fordelivery of one or more therapeutic agents. In some embodiments, thelumen may be of any suitable diameter. In some embodiments, the lumendiameter is maximized with respect to the outer catheter diameter. Insome embodiments, the lumen size is irrespective of the outer catheterdiameter (e.g. significantly smaller inner lumen than outer catheterdiameter). In some embodiments, an inner lumen diameter is 0.1 mm to 12mm (e.g. 0.1 mm . . . 0.2 mm . . . 0.5 mm . . . 1.0 mm . . . 2.0 mm . .. 5.0 mm . . . 10 mm . . . 12.0 mm, and diameters therein). In someembodiments, a catheter comprises a plurality of inner lumens (U.S. Pat.No. 7,037,290, herein incorporated by reference in its entirety). Insome embodiments, catheter lumens are configured for therapeuticdelivery, therapeutic storage, encasing electrophysiology devices,encasing electronics, providing catheter steering/movement elements,interacting with a catheter balloon element, etc. In some embodiments, acatheter comprises multiple lumens configured for multiple functions.

In some embodiments, the present invention comprises a balloon (e.g.isolation balloon, electroporation balloon, orientation balloon,ultrasound balloon, etc.). In some embodiments, the present inventioncomprises a balloon which provides one or more functionalitiesincluding, but not limited to, physical isolation of catheter fromtissues, thermal isolation of tissues (e.g. isolation of tissues thataren't the intended site of energy delivery), enhancing surface area ofelectrodes, positioning electrodes around delivery site, acting as apseudo-electrode, orienting the catheter tip at the delivery site,providing pressure between electrodes and delivery site, deliveringultrasound energy, opening potential-spaces ahead of the catheter tip,etc. In some embodiments, a balloon is located at or near the cathetertip. In some embodiments, the balloon may be positioned anywhere alongthe length of the catheter. In some embodiments, multiple balloons (e.g.2, 3, 4, 5, 6, 7, 8, 9, 10 . . . 20 . . . 50, etc.) are positioned alongthe length of a catheter. In embodiments comprising multiple balloons,the balloons may be of the same or different sizes and/or shapes. Insome embodiments, a balloon associated with a catheter of the presentinvention is of any useful shape (e.g. round, oval, flat, cylindrical,etc.) and/or size. In some embodiments, a balloon is a flatpancake-shape (i.e., the depth is less than the width; e.g., by a ratioof 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 20:1, etc.). In someembodiments, the balloon is a standard inflatable percutaneousintervention balloon (e.g., a venoplasty balloon). In some embodiments,a pancake-shaped balloon is wider than it is deep (e.g., 1.5× wider thandeep; 2× wider than deep; 5× wider than deep; 10× wider than deep; 25×wider than deep). In some embodiments, a balloon is tall and narrow(e.g., 1.5× taller than wide; 2× taller than wide; 3× taller than wide;5× taller than wide; 10× taller than wide; 25× taller than wide). Insome embodiments, a balloon has dimensions (height, width, and/orlength) of approximately 1-50 mm (e.g. 1 mm . . . 2 mm . . . 5 mm . . .10 mm . . . 20 mm . . . 30 mm . . . 40 mm . . . 50 mm). In someembodiments, the height, width, and/or length of a balloon comprise thesame dimensions or different dimensions. In some embodiments, theballoon is filled with fluid (e.g. gas or liquid). In some embodiments,the balloon is saline filled. In some embodiments, the balloon isconfigured for active saline exchange to provide additional thermalprotection. In some embodiments, a balloon surrounds the catheter,allowing the catheter to deliver material through a lumen running withinthe balloon. In some embodiments, the lumen of the catheter and insideof the balloon are provided as separate spaces. In some embodiments,fluids (e.g. liquids or gasses) within the catheter lumen cannot passinto the balloon. In some embodiments, fluids (e.g. liquids or gasses)within the balloon's interior cannot pass into the catheter lumen. Insome embodiments, a catheter comprises an inflation lumen, separate fromthe delivery lumen of the catheter, configured to deliver one or morefluids (e.g. liquids and/or gasses) to inflate the balloon within asubject and/or adjacent to a delivery site. In some embodiments, theballoon may be partially or fully inflated or deflated.

In some embodiments the present invention comprises a balloon configuredfor isolation and/or orientation of the catheter. In some embodiments,an orientation balloon, isolation balloon, and/or isolation/orientationballoon is provided. In some embodiments, the balloon is configured toadjust to the shape of a tissue region. In some embodiments, the balloonis configured to maintain the proper orientation of the catheter withinthe desired location. In some embodiments, the balloon is configured toisolate the delivery site from surrounding tissues and structures. Insome embodiments, a balloon is configured to physically isolate thecatheter tip from surrounding tissues (e.g. non-delivery-site tissues).In some embodiments, the balloon physically moves surrounding tissue orstructures away from the delivery site. In some embodiments the balloonis configured to provide a thermal barrier that will minimize damage toadjacent tissue and structures from thermal radiant energy (e.g. duringelectroporation or ultrasound application). In some embodiments, aballoon thermally isolates surrounding tissues (e.g. non-delivery-sitetissues) from the catheter tip. In some embodiments, the balloonprovides pressure between tissue at the delivery site and the catheterelements (e.g. electrodes, sonoporation element). In some embodiments,the balloon provides pressure between tissue at the delivery site andthe catheter elements (e.g. electrodes, piezoelectric crystals,injection needle, etc.) to enhance the effect of energy delivery ormaterial delivery.

In some embodiments, the present invention provides a balloon configuredto deliver electroporation energy, sonoporation energy, and/or monitorelectrical signals. In some embodiments, an electroporation balloon isprovided (SEE FIG. 10). In some embodiments, a sonoporation balloon isprovided. In some embodiments, an electroporation balloon is located atthe distal end of a catheter. In some embodiments, one or moreelectrodes (e.g. electroporation electrodes, monitoring electrodes,etc.) are mounted on or in an electroporation balloon (e.g. 1 electrode,2 electrodes, 3 electrodes, 4 electrodes, 5 electrodes . . . 10electrodes . . . 20 electrodes . . . 30 electrodes . . . 50 electrodes .. . 100 electrodes, etc.). In some embodiments, one or more (e.g. 1, 2,3, 4, 5 . . . 10 . . . 20 . . . 50 . . . 100, etc.) electroporationelectrodes are mounted on and/or in an electroporation balloon. In someembodiments, electroporation electrodes (e.g. 1 electrode, 2 electrodes,3 electrodes, 4 electrodes, 5 electrodes . . . 10 electrodes . . . 20electrodes . . . 30 electrodes . . . 50 electrodes . . . 100 electrodes,etc.) are equally spaced along a ring around the distal end of thecatheter (e.g. catheter opening, injection needle, etc.). In someembodiments, one or more monitoring electrodes are located between eachset of electroporation electrodes. In some embodiments, one or more(e.g. 1, 2, 3, 4, 5 . . . 10 . . . 20 . . . 50 . . . 100) monitoringelectrodes are mounted on and/or in an electroporation balloon. In someembodiments a combination of monitoring and electroporation electrodesare mounted on and/or in an electroporation balloon. In someembodiments, electrodes mounted on an electroporation balloon areconfigured to adopt a defined pattern (e.g. circle, oval, line, etc.)when the electroporation balloon is inflated and/or substantiallyinflated. In some embodiments, an inflated electroporation balloonplaces electrodes in direct contact with tissue at the delivery site. Insome embodiments, an inflated electroporation balloon places electrodesin direct contact with tissue surrounding the delivery site. In someembodiments, an inflated electroporation balloon places electrodes indirect contact with delivery site tissue while protectingnon-delivery-site tissue. In some embodiments, electrodes are positionedaround the catheter opening at the distal end of a catheter (e.g.delivery or injection end of a catheter). In some embodiments, when anelectroporation balloon is inflated, electrodes form a ring around thedelivery end (e.g. injection needle) of the catheter. In someembodiments, the ring of electrodes on an inflated electroporationballoon is of any suitable diameter (e.g. 2 mm . . . 5 mm . . . 1 cm . .. 2 cm . . . 5 cm, etc.). In some embodiments, the ring of electrodes onan inflated electroporation balloon is of any suitable interelectrodediameter (e.g. 2 mm . . . 5 mm . . . 1 cm . . . 2 cm . . . 5 cm, etc.).In some embodiments, electroporation electrodes and monitoringelectrodes form a single ring. In some embodiments, a ring of monitoringelectrodes is provided. In some embodiments, a ring of electroporationelectrodes is provided. In some embodiments, an electroporation balloonenhances, increases, and/or expands the area of contact between theelectrodes and the delivery-site tissue (e.g. myocardium). In someembodiments, an electroporation balloon, when inflated and in contactwith delivery-site tissue (e.g. atrial myocardium), allow the monitoringelectrodes to record electric activity (e.g. atrial activity) fromseveral sites over its contact area. In some embodiments, gene injectionis performed from the catheter within the ring of electrodes around thecircumference of the expanded (e.g. inflated) electroporation balloon.In some embodiments, an electroporation balloon also provides isolation(e.g. physical, thermal, etc.) and/or orientation functions.

In some embodiments, the present invention provides a balloon configuredto deliver ultrasound energy and/or monitor electrical signals. In someembodiments, an ultrasound balloon is provided (SEE FIG. 11). In someembodiments, an ultrasound balloon provides ultrasound energy tosurrounding tissues. In some embodiments, an ultrasound balloon providesultrasound energy to tissues at the delivery site. In some embodiments,an ultrasound balloon provides ultrasound energy to facilitate genetransfer into surrounding tissues. In some embodiments, piezoelectriccrystals are housed in, within, and/or on an ultrasound balloon. In someembodiments, piezoelectric ceramics are housed in, within, and/or on anultrasound balloon. In some embodiments, electric current is applied topiezoelectric crystals to generate ultrasound energy. In someembodiments, ultrasound energy is used to enhance and/or facilitate genetransfer. In some embodiments, ultrasound energy is delivered to thedelivery site to enhance and/or facilitate gene transfer (e.g. at themyocardium). In some embodiments, a device comprising an ultrasoundballoon provides ultrasound-mediated gene transfer, a technique which isunderstood in the field (Yoon and Park. Expert Opin Drug Deliv. 2010March; 7(3):321-30.; Wells. Cell Biol Toxicol. 2010 February;26(1):21-8.; herein incorporated by reference in their entireties). Insome embodiments a combination of monitoring electrodes and ultrasoundcrystals are mounted on and/or in an ultrasound balloon. In someembodiments, ultrasound crystals mounted on an ultrasound balloon areconfigured to adopt a defined pattern (e.g. circle, oval, line, etc.)when the ultrasound balloon is inflated and/or substantially inflated.In some embodiments, an inflated ultrasound balloon places piezoelectriccrystals in direct contact with tissue at the delivery site. In someembodiments, an inflated ultrasound balloon places piezoelectriccrystals in direct contact with tissue surrounding the delivery site. Insome embodiments, an inflated ultrasound balloon places piezoelectriccrystals in direct contact with delivery site tissue while protectingnon-delivery-site tissue. In some embodiments, piezoelectric crystalsare positioned around the catheter opening at the distal end of acatheter (e.g. delivery or injection end of a catheter). In someembodiments, when an ultrasound balloon is inflated, piezoelectriccrystals are positioned around the delivery end (e.g. injection needle)of the catheter. In some embodiments, the field of piezoelectriccrystals on an inflated ultrasound balloon is of any suitable diameter(e.g. 2 mm . . . 5 mm . . . 1 cm . . . 2 cm . . . 5 cm, etc.). In someembodiments, monitoring electrodes are located within, at the perimeterof, or near the field of piezoelectric crystals. In some embodiments, anultrasound balloon enhances, increases, and/or expands the area ofcontact between the piezoelectric crystals and the delivery-site tissue(e.g. myocardium). In some embodiments, an ultrasound balloon, wheninflated and in contact with delivery-site tissue (e.g. atrialmyocardium), allows the monitoring electrodes to record electricactivity (e.g. atrial activity) from several sites over its contactarea. In some embodiments, gene injection is performed from the catheterwithin the field of piezoelectric crystals around the circumference ofthe expanded (e.g. inflated) ultrasound balloon. In some embodiments, anultrasound balloon also provides isolation (e.g. physical, thermal,etc.) and/or orientation functions.

In some embodiments, the present invention provides a catheter fordelivering an energy-delivery probe (e.g., electroporation probe,sonoporation probe, etc.) to a site within the body in order to performelectroporation and/or sonoporation at the site. In some embodiments,the present invention provides electroporation and/or sonoporation atthe site of therapeutic delivery within a subject. In some embodiments,a catheter provides both electroporation and therapeutic delivery. Insome embodiments, a catheter provides both sonoporation and therapeuticdelivery. In some embodiments, a catheter provides both electroporationand sonoporation. In some embodiments, a catheter provides sonoporation,electroporation, and therapeutic delivery. In some embodiments, thecatheter is configured to carry an energy-delivery probe (e.g.,electroporation probe, sonoporation probe, etc.) near the distal end ofthe catheter. In some embodiments, the catheter and energy-deliveryprobe (e.g., electroporation probe, sonoporation probe, etc.) comprise asingle unit (e.g. electroporation catheter, sonoporation catheter,etc.). In some embodiments, the catheter comprises means for attachingthe energy-delivery probe (e.g., electroporation probe, sonoporationprobe, etc.). In some embodiments, the energy-delivery probe (e.g.,electroporation probe, sonoporation probe, etc.) is located on thedistal end of the catheter. In some embodiments, the energy-deliveryprobe (e.g., electroporation probe, sonoporation probe, etc.) isdelivered to the body site where electroporation and/or sonoporation areto be performed. In some embodiments, the distal end of the catheter ispositioned over tissue at the electroporation site. In some embodiments,a catheter delivers the electroporation and/or sonoporation energy tothe tissue in contact therewith. In some embodiments, a catheter may beessentially straight although it may also be curved or define a closedloop. In some embodiments, the utility for delivering energy (e.g.,electric energy, ultrasound energy, etc.) to the catheter is eitherlinked to the catheter or is associated therewith in an inductionassociation to permit the delivery of energy to the catheter. A personversed in the art is able to determine both the intensity of the energy(e.g., electric energy, ultrasound energy, etc.) and the length of timefor its application. This may be determined, for example, on the basisof either the scientific literature relating to such techniques, theoperators own experience, or through empirical testing.

In some embodiments, the present invention provides a catheter fordelivering an ultrasound probe (e.g., sonoporation probe) to a sitewithin the body in order to perform ultrasound-mediated therapeutictransfer at the site (e.g. ultrasound-mediated gene transfer,sonoporation, etc.). In some embodiments, the present invention providesultrasound at the site of therapeutic delivery within a subject. In someembodiments, a catheter provides both ultrasound and therapeuticdelivery (e.g. gene delivery). In some embodiments, the catheter isconfigured to carry an ultrasound probe (e.g. ultrasound balloon,sonoporation probe, etc.) near the distal end of the catheter. In someembodiments, the catheter and probe comprise a single unit (e.g.ultrasound catheter). In some embodiments, the catheter comprises meansfor attaching the ultrasound probe (e.g. delivery catheter andultrasound probe). In some embodiments, the ultrasound probe (e.g.ultrasound balloon) is located on the distal end of the catheter. Insome embodiments, the ultrasound probe (e.g. ultrasound balloon) isdelivered to the body site where ultrasound application is to beperformed. In some embodiments, the distal end of the catheter ispositioned over tissue at the ultrasound-application site. In someembodiments, the ultrasound catheter delivers the ultrasound energy tothe tissue in contact therewith. In some embodiments, the ultrasoundcatheter may be essentially straight although it may also be curved ordefine a closed loop. In some embodiments, the utility for deliveringultrasound energy to the catheter is either linked to the catheter or isassociated therewith in an induction association to permit the deliveryof ultrasound energy to the catheter. A person versed in the art is ableto determine both the intensity of the ultrasound energy and the lengthof time for its application. This may be determined, for example, on thebasis of either the scientific literature relating to ultrasound-mediategene transfer techniques, or the operators own experience.

In some embodiments, the present invention provides a catheter fordelivering an electroporation probe to a site within the body in orderto perform electroporation-mediated therapeutic transfer at the site(e.g. electroporation-mediated gene transfer). In some embodiments, thepresent invention provides electroporation at the site of therapeuticdelivery within a subject. In some embodiments, a catheter provides bothelectroporation and therapeutic delivery (e.g. gene delivery). In someembodiments, the catheter is configured to carry an electroporationprobe near the distal end of the catheter. In some embodiments, thecatheter and probe comprise a single unit (e.g. electroporationcatheter). In some embodiments, the catheter comprises means forattaching the electroporation probe (e.g. delivery catheter andelectroporation probe). In some embodiments, the electroporation probeis located on the distal end of the catheter. In some embodiments, theelectroporation probe is delivered to the body site where ultrasoundapplication is to be performed. In some embodiments, the distal end ofthe catheter is positioned over tissue at theelectroporation-application site. In some embodiments, theelectroporation catheter delivers the electric energy to the tissue incontact therewith. In some embodiments, the electroporation catheter maybe essentially straight although it may also be curved or define aclosed loop. In some embodiments, the utility for delivering electricenergy to the catheter is either linked to the catheter or is associatedtherewith in an induction association to permit the delivery of electricenergy to the catheter. A person versed in the art is able to determineboth the intensity of the electric energy and the length of time for itsapplication. This may be determined, for example, on the basis of eitherthe scientific literature relating to ultrasound-mediate gene transfertechniques, or the operators own experience.

In some embodiments, the present invention provides a catheter fordelivering an electrophysiology probe to a site within the body in orderto record or monitor electrical signals at the site. In someembodiments, the present invention records or monitors electricalsignals at the site of therapeutic delivery within a subject. In someembodiments, a catheter provides both electrophysiology recordation andtherapeutic delivery. In some embodiments, the catheter is configured tocarry an electrophysiology probe near the distal end of the catheter. Insome embodiments, the catheter and probe comprise a single unit (e.g.electrophysiology catheter). In some embodiments, the catheter comprisesmeans for attaching the electrophysiology probe (e.g. delivery catheterand electrophysiology probe). In some embodiments, the electrophysiologyprobe is located on the distal end of the catheter. In some embodiments,the electrophysiology probe is delivered to the body site whererecording of electrical signals is to be performed. In some embodiments,the distal end of the catheter is positioned over tissue at theelectrophysiologic monitoring site. In some embodiments, theelectrophysiology catheter records the electrophysiology energy of thetissue in contact therewith. In some embodiments, the utility forrecording electrophysiology energy is either linked to the catheter oris associated therewith. A person versed in the art is able to determinetechniques and means for recording electrical signals within a subjectThis may be determined, for example, on the basis of either thescientific literature relating to electrophysiology techniques, or theoperators own experience.

In some embodiments, the present invention provides delivery oftherapeutics (e.g. pharmaceuticals, gene therapy, small molecules,nucleic acid, peptides, etc.). In some embodiments, catheter devicesprovide a delivery means for localized administration of therapeutics,thereby reducing side effects from systemic administration. In someembodiments, therapeutics of the present invention comprise smallmolecule drugs, peptides, nucleic acids (e.g. DNA, RNA, genes,minigenes, RNAi, etc.). In some embodiments, the present invention findsutility in the targeted delivery of gene therapy reagents (e.g. DNA,minigenes, naked DNA, viral vector, etc.). In some embodiments, preciseplacement of gene therapy reagents increases efficiency of theirincorporation into cells and/or their effectiveness in treating adisease or disorder. In some embodiments, the present invention utilizeselectroporation and/or sonoporation to facilitate therapeutic uptakeinto target cells. In some embodiments, the present invention utilizeselectroporation and/or sonoporation to increase the efficiency oftherapeutic uptake into target cells. In some embodiments, the presentinvention provides electroporation and/or sonoporation in conjunctionwith gene therapy (e.g. delivery of DNA (e.g. naked DNA). In someembodiments, electroporation and/or sonoporation increases theefficiency of gene delivery in gene therapy. In some embodiments,electroporation in and/or sonoporation conjunction with gene therapyincreases the treatment effectiveness of the gene therapy treatment. Insome embodiments, electroporation and/or sonoporation enhances genetransfer. In some embodiments, electroporation enhances entry oftherapeutics (e.g. gene therapy reagents, nucleic acid, peptides,minigenes, DNA, etc.) into target cells. In some embodiments, thepresent invention utilizes electric and/or ultrasound energy tofacilitate therapeutic uptake into target cells. In some embodiments,the present invention utilizes electric and/or ultrasound energy toincrease the efficiency of therapeutic uptake into target cells. In someembodiments, the present invention provides application of electricand/or ultrasound energy in conjunction with gene therapy (e.g. deliveryof DNA (e.g. naked DNA). In some embodiments, ultrasound energyincreases the efficiency of gene delivery in gene therapy. In someembodiments, application of electric and/or ultrasound energy inconjunction with gene therapy increases the treatment effectiveness ofthe gene therapy treatment. In some embodiments, application of electricand/or ultrasound energy enhances gene transfer. In some embodiments,application of electric and/or ultrasound energy enhances entry oftherapeutics (e.g. gene therapy reagents, nucleic acid, peptides,minigenes, DNA, etc.) into target cells.

In some embodiments, the present invention provides a means for treatinga subject. In some embodiments, catheters of the present inventionprovide therapeutic delivery and electroporation and/or sonoporation totreat a subject. In some embodiments, catheters of the present inventionprovide therapeutic delivery and application of electric and/orultrasound energy to treat a subject. In some embodiments, the presentinvention provides localized treatment. In some embodiments, use of thepresent invention avoids systemic delivery of therapeutics, insteaddelivering therapeutics to the desired site of action. In someembodiments, electroporation and/or sonoporation increases theefficiency of therapeutic uptake into cells. In some embodiments,electroporation and/or sonoporation increase the efficiency of genetherapy. In some embodiments, a device introduces an electric current(e.g. 0.5 to 1 V) to a therapeutic delivery site. In some embodiments,electroporation increases the permeability of the cells in the localregion of the electric current. In some embodiments, sonoporationincreases the permeability of the cells in the local region of theultrasound energy. In some embodiments, electroporated and/orsonoporated cells are more readily available for uptake of therapeutics(e.g. DNA). In some embodiments, monitoring of electrical signals beforeand after administration of therapeutics, sonoporation, and/orelectroporation provides a method for monitoring the effectiveness oftreatment. In some embodiments, electrophysiology results allowclinicians to monitor the course of treatment or treatments using adevice of the present invention and/or other medical treatments.

The catheter shaft can be of any suitable construction and made of anysuitable material. In some embodiments, devices, systems, and/orcomponents of the present invention comprise materials such as CoCrMoalloy, Titanium alloy, cpTi, Ti6Al4V ELI medical grade stainless steel,Tantalum, Tantalum alloy, Nitinol, polymers, alloys, metals, ceramics,oxides, minerals, glasses and combinations thereof. In preferredembodiments, materials are selected based on desirability ofbiomechanical properties and interaction with surrounding biologicalenvironment of the device and/or system. In some embodiments, materialsare selected based on the specific application, requirements, and/ordeployment location. In some embodiments, devices, systems, and/or othercomponents of the present invention comprise one or more metals, alloys,plastics, polymers, natural materials, synthetic materials, fabrics,etc. In some embodiments, devices, systems, and/or other components ofthe present invention comprise one or more metals including but notlimited to aluminum, antimony, boron, cadmium, cesium, chromium, cobalt,copper, gold, iron, lead, lithium, manganese, mercury, molybdenum,nickel, platinum, palladium, rhodium, silver, tin, titanium, tungsten,vanadium, and zinc. In some embodiments, devices, systems, and/or othercomponents of systems of the present invention comprise one or morealloys including but not limited to alloys of aluminium (e.g., Al—Li,alumel, duralumin, magnox, zamak, etc.), alloys of iron (e.g., steel,stainless steel, surgical stainless steel, silicon steel, tool steel,cast iron, Spiegeleisen, etc.), alloys of cobalt (e.g., stellite,talonite, etc.), alloys of nickel (e.g., German silver, chromel,mu-metal, monel metal, nichrome, nicrosil, nisil, nitinol, etc.), alloysof copper (beryllium copper, billon, brass, bronze, phosphor bronze,constantan, cupronickel, bell metal, Devarda's alloy, gilding metal,nickel silver, nordic gold, prince's metal, tumbaga, etc.), alloys ofsilver (e.g., sterling silver, etc.), alloys of tin (e.g., Britannium,pewter, solder, etc.), alloys of gold (electrum, white gold, etc.),amalgam, and alloys of lead (e.g., solder, terne, type meta, etc.). Insome embodiments, devices, systems, and/or other components of thepresent invention comprise one or more plastics including but notlimited to Bakelite, neoprene, nylon, PVC, polystyrene,polyacrylonitrile, PVB, silicone, rubber, polyamide, synthetic rubber,vulcanized rubber, acrylic, polyethylene, polypropylene, polyethyleneterephthalate, polytetrafluoroethylene, gore-tex, polycarbonate, etc. Insome embodiments, elements of a device of the present invention may alsocomprise glass, textiles (e.g., from animal, plant, mineral, and/orsynthetic sources), liquids, etc. In some embodiments, a suitableconstruction includes, but is not limited to, an outer wall made ofpolyurethane, TEFLON, HDPE, nylon, PEEK, PTFE, PEBAX, or other suitablematerials.

In some embodiments, a catheter of the present invention is insertedinto a lumen within a subject (e.g., vein, artery, gastrointestinaltract, lumen of an organ, etc.) and/or maneuvered through a lumen of asubject. In some embodiments, a catheter of the present invention isinserted into an artery of a subject and/or maneuvered through an arteryof a subject. In some embodiments, a catheter of the present inventionis inserted into and/or maneuvered through an artery or arteriesincluding, for example, the ascending aorta, right coronary artery, leftcoronary artery, anterior interventricular, circumflex, left marginalarteries, posterolateral artery, intermedius, arch of aorta,brachiocephalic artery, common carotid artery, internal carotid artery,external carotid artery, subclavian artery, vertebral artery, internalthoracic artery, thyrocervical trunk, deep cervical artery, dorsalscapular artery, brachial artery, thoracic aorta, abdominal aorta,inferior phrenic, celiac, superior mesenteric, middle suprarenal, renal,anterior and posterior, interlobar artery, gonadal, lumbar, inferiormesenteric, median sacral, common iliac, common iliac arteries, internaliliac artery, anterior division, obturator artery, superior vesicalartery, vaginal artery (females), inferior vesical artery (males),middle rectal artery, internal pudendal artery, inferior gluteal artery,uterine artery (females), deferential artery (males), (obliterated)umbilical artery, posterior division, iliolumbar artery, lateral sacralartery, superior gluteal artery, external iliac artery, inferiorepigastric artery, deep circumflex iliac artery, femoral artery,superficial epigastric artery, superficial circumflex iliac artery,superficial external pudendal artery, deep external pudendal artery,deep femoral artery, descending genicular artery, popliteal artery,anterior tibial artery, posterior tibial artery, sural artery, medialsuperior genicular artery, lateral superior genicular artery, middlegenicular artery, inferior lateral, and inferior medial genicularartery. In some embodiments, a catheter of the present invention isinserted into a vein of a subject and/or maneuvered through a vein of asubject. In some embodiments, a catheter of the present invention isinserted into and/or maneuvered through an vein or veins including, forexample, the internal jugular, external jugular, subclavian, axillary,cephalic, brachial, basilica, radial, ulnar, renal, brachiocephalic,superior vena cava, hepatic, hepatic portal, common iliac, externaliliac, femoral, great saphenous, popliteal, posterior tibial, anteriortibial, small saphenous, dorsal venous arch, etc.

In some embodiments, the present invention provides devices and methodsfor material delivery (e.g., gene delivery), electroporation,sonoporation, and/or monitoring electrophysiological activity at atissue (e.g., cardiac tissue, muscle tissue, dermal tissue, etc.), organ(e.g., heart), organ system (circulatory system, digestive tract,nervous system, etc.), etc. In some embodiments, material delivery,electroporation, sonoporation, and/or monitoring electrophysiologicalactivity are performed in one or more layers of the heart (e.g.endocardium, myocardium, epicardium, etc.). In some embodiments, accessis provided by devices of the present invention to the endocardium,myocardium, and/or epicardium. In some embodiments, materials (e.g.,therapeutics, nucleic acids, etc.) are delivered via devices of thepresent invention to the endocardium, myocardium, epicardium, etc. Insome embodiments, sonoporation and/or electroporation energy aredelivered via devices of the present invention to the endocardium,myocardium, and/or epicardium. In some embodiments, theelectrophysiological activity of the endocardium, myocardium, and/orepicardium are monitored. In some embodiments, the electrophysiologicalactivity of the endocardium, myocardium, and/or epicardium are monitoredfollowing delivery of materials (e.g., therapeutics, nucleic acids,etc.), sonoporation, and/or electroporation. In some embodiments,materials (e.g., therapeutics, nucleic acids, etc.) are delivered to,sonoporation and/or electroporation are applied to, and/orelectrophysiological activity is monitored in the endocardium of theheart of subject (e.g., mammal, human, etc.). In some embodiments, thepresent invention provides devices for targeting endothelial cells(e.g., of the endocardium) with materials (e.g., therapeutics, nucleicacids, etc.), electroporation, sonoporation, and/or electrophysiologicalactivity measurements. In some embodiments, materials (e.g.,therapeutics, nucleic acids, etc.) are delivered to, sonoporation and/orelectroporation are applied to, and/or electrophysiological activity ismonitored in the epicardium of the heart of subject (e.g., mammal,human, etc.). In some embodiments, materials (e.g., therapeutics,nucleic acids, etc.) are delivered to, sonoporation and/orelectroporation are applied to, and/or electrophysiological activity ismonitored in the myocardium of the heart of subject (e.g., mammal,human, etc.). In some embodiments, materials (e.g., therapeutics,nucleic acids, etc.) are delivered to, sonoporation and/orelectroporation are applied to, and/or electrophysiological activity ismonitored in non-cardiac (e.g., non-cardiac circulatory system tissues,non-circulatory system tissues and organs, etc.) systems, organs,tissues, and/or cells. In some embodiments, materials (e.g.,therapeutics, nucleic acids, etc.) are delivered to, sonoporation and/orelectroporation are applied to, and/or electrophysiological activity ismonitored in tissues, organs and/or cells in the digestive system (e.g.,tissues and/or organs of the alimentary canal), respiratory system(e.g., lungs, etc.), circulatory system (e.g., veins, arteries, etc.),musculoskeletal system (e.g., muscle tissue, connective tissue, etc.),and/or nervous system (e.g., brain, nerves, spinal cord, etc.). In someembodiments, a device of the present invention accesses delivery sitesvia veins arteries, other body lumens (e.g., digestive tract (e.g.,orally, rectally, etc.), subcutaneously, other suitable routes, andcombinations thereof.

In some embodiments, the present invention provides devices,compositions, and methods for treatment, diagnosis, or monitoring ofdiseases and/or conditions. The catheter devices, catheter systems, andmethods of the present invention may be used with any subject orpatient, including, but not limited to, humans, non-human primates,mammals, feline, canine, bovine, equine, porcine, rodent, etc. In someembodiments, the subject is a human requiring treatment for a medicalcondition. In some embodiments, the subject is a human or other mammalsuffering from a condition, disease, or disorder delivery of atherapeutic agent (e.g. gene therapy) to a specific location within thesubject provides treatment. In some embodiments, the subject is a humanor other mammal undergoing surgery or catheter based diagnostic ortherapeutic procedures. In addition, any body region may be used withthe catheter devices, catheter systems, kits, and methods of the presentinvention.

In some embodiments, the present invention provides devices and methodsfor treating diseases, disorders and conditions in a subject. In someembodiments, the present invention provides devices and methods fortreating diseases and disorders in any body regions or locations thatare accessible by catheter. In some embodiments, the present inventionprovides devices and methods for treating heart conditions (e.g. rhythmdisturbances (e.g. atrial fibrillation)). In some embodiments, thepresent invention provides compositions and methods to treat or preventconditions and/or diseases of the heart (e.g. rhythm disturbances (e.g.atrial fibrillation)). In some embodiments, the present inventionprovides treatment or prevention of a heart disease or conditionselected from the list of aortic dissection, cardiac arrhythmia (e.g.atrial cardiac arrhythmia (e.g. premature atrial contractions, wanderingatrial pacemaker, multifocal atrial tachycardia, atrial flutter, atrialfibrillation, etc.), junctional arrhythmias (e.g. supraventriculartachycardia, AV nodal reentrant tachycardia, paroxysmalsupra-ventricular tachycardia, junctional rhythm, junctionaltachycardia, premature junctional complex, etc.), atrio-ventriculararrhythmias, ventricular arrhythmias (e.g. premature ventricularcontractions, accelerated idioventricular rhythm, monomorphicventricular tachycardia, polymorphic ventricular tachycardia,ventricular fibrillation, etc.), etc.), congenital heart disease,myocardial infarction, dilated cardiomyopathy, hypertrophiccardiomyopathy, aortic regurgitation, aortic stenosis, mitralregurgitation, mitral stenosis, Ellis-van Creveld syndrome, familialhypertrophic cardiomyopathy, Holt-Orams Syndrome, Marfan Syndrome,Ward-Romano Syndrome, and/or similar diseases and conditions. In someembodiments, the present invention provides methods for blocking Gprotein coupled receptor mediated signaling for treating atrialfibrillation (see, U.S. application Ser. No. 12/430,595, hereinincorporated by reference in its entirety).

Both sympathetic and parasympathetic activity in the heart is mediatedby heterotrimeric G-protein (GαGα3Gα) coupled pathways initiated byG-protein coupled receptors (GPCRs). In some embodiments, the presentinvention provides a gene-based approach to selectively inhibit theG-protein signaling pathways. In some embodiments, the present inventionis used in an epicardial approach to administer minigenes expressingG-protein inhibitory peptides to the PLA, in order to selectivelyinhibit the C-terminus of Gαi and Gαs in this region. In someembodiments, the present invention provides electroporation and/orultrasound energy to enhance the effectiveness of gene therapy (e.g.,for naked DNA and/or viral vectors). In some embodiments,electroporation and/or ultrasound energy enhance intracellular genetransfer (e.g. within the PLA). In some embodiments, the presentinvention targets G-protein mediated autonomic signaling, and/or otherkey signal transduction pathways (e.g. the TGF-beta pathway in thecreation of atrial fibrosis). In some embodiments, the present inventionprovides a targeted gene-based approach to attenuate TGF-beta signalingin the left atrium, in order to decrease the development of fibrosis inAF.

In some embodiments, the present invention provides a non-surgical,minimally invasive approach. In some embodiments, the present inventionprovides a clinical gene-based approach. In some embodiments, thepresent invention provides a minimally invasive, transvenous(transseptal) approach to achieve gene delivery (e.g. within the leftatrium (e.g. in the PLA)). In some embodiments, the present inventionprovides safe and effective gene delivery (e.g. to the atrium) via apercutaneous, transvenous approach. In some embodiments, the presentinvention provides delivery of therapeutics including gene-basetherapies, cell-based therapies, or pharmacological therapies. In someembodiments, the present invention provides electroporation as anefficient method for transfer of naked DNA into cells (e.g. in the PLA).In some embodiments, the present invention provides application ofultrasound energy as an efficient method for transfer of naked DNA intocells (e.g. in the PLA). In some embodiments, the present inventionprovides targeted and efficient gene transfer (e.g. in the PLA) via atransvenous, endocardial approach.

In some embodiments, devices include at least one tissue contactingmember for contacting a tissue or organ surface (e.g., epicardialtissue) and securing the device to the surface. In some embodiments,devices include at least one cardiac-contacting member for contacting acardiac surface (e.g., epicardial tissue, endocardial tissue) andsecuring the device to the surface. In one aspect, a system for treatingheart tissue to treat a cardiac arrhythmia comprises: at least oneenergy-delivery element for applying energy to the heart tissue; atleast one tissue securing member (e.g., clamp, balloon, suction, etc.)coupled with the at least one energy-delivery element for enhancingcontact of the energy-delivery element with the heart tissue; and atleast one guiding member coupled with at least one of theenergy-delivery element and the tissue securing member for guiding theenergy-delivery element and the tissue securing member to a location fortreating the heart tissue. In some embodiments, treating the hearttissue comprises applying energy to the heart tissue in a pattern toreduce or eliminate the cardiac arrhythmia. In some embodiments,treating the heart tissue comprises applying energy to the heart tissueto aid in therapeutic uptake (e.g., through electroporation and/orsonoporation). The applied energy may be in any suitable form, such asradio frequency energy, ultrasound energy, microwave energy, cryogenicenergy, thermoelectric energy or laser energy. In some embodiments, theenergy is applied to an epicardial surface of the heart. In someembodiments, the energy is applied to an endocardial surface of theheart. In some embodiments, the energy is applied to an epicardialsurface of the heart, wherein the energy is transmitted from theepicardial surface through the heart tissue to an endocardial surface.Optionally, the energy may be further transmitted through fat and/orconnective tissue to access the treatment site.

EXPERIMENTAL Example 1 Denervation of the PLA with Minigene ExpressingGai Inhibitory Peptide

Experiments were conducted during development of the present inventionwith minigene expressing Gαi peptide in a model of AF, which demonstratethat epicardial injection (using an open-chest approach) of minigenesexpressing Gαi peptides into the PLA followed by electroporation resultsin: a) successfully transcription of the minigene with production of Gαipeptide and 2) inhibit of vagal responsiveness in the entire leftatrium.

High-density epicardial mapping was performed in canine subjects using2×2 electrodes in the PVs, 7×3 electrodes in the PLA, and 7×3 electrodesin the left atrial appendage (LAA). Effective refractory periods (ERPs)were obtained at baseline and in response vagal stimulation (VS)(20 Hz).After baseline mapping, 1 mg (in a volume of up to 2 ml) of eitherFLAG-tagged Gαi1/2 expressing minigene, or FLAG-tagged GαR (randompeptide) expressing minigene was injected into the PLA. The PLA was thensubjected to electroporation using the electrodes (SEE FIG. 1).Epicardial mapping was performed again 48-72 hours after minigeneinjection. RNA was isolated from frozen heart tissue for PCR and RT-PCR.Western blotting and immunostaining were performed for FLAG-taggedpeptide.

Gene Expression in the PLA.

FIG. 2A shows the results of PCR on PLA tissue injected with theminigene. Lanes 5 shows the presence of minigene mRNA in PLA tissue (434bp and denoted by arrow), indicating successful transcription of theminigene. FIG. 2B shows the results of RT-PCR; the bar-graph showsexpression of the minigene only in the PLA (the site of minigeneinjection), and not in the LAA (remote from injection site). FIG. 3shows a representative western blot for FLAG-tagged Gαi peptide. Theblot shows expression of FLAG in the PLA (the site of gene injection)but no FLAG expression remote from the site of injection (LAA). FIG. 4shows the results of immunostaining for FLAG-tagged Gαi1/2 peptide.Peptide expression was noted both in cardiomyocytes as well as in nervebundles/ganglion cells. Panels A and B show the presence of Gαi peptidein a nerve bundle and in the myocardium of the PLA (heavy brown stain).In contrast, as shown in panel C, there is no peptide, as evidenced bythe lack of heavy brown stain in the adjoining LAA, which is remote fromgene injection site, therefore serving as a negative control.

Functional Effects of Gαi1/2 Minigene.

FIG. 5 shows the effects of Gαi1/2 minigene on vagal-induced ERPshortening. Significant VS-induced ERP shortening was noted at baselinein each dog. However, VS-induced ERP shortening was markedly attenuatedafter Gαi minigene injection. Vagal-induced AF inducibility was alsosignificantly diminished after Gα1/2 minigene injection (SEE FIG. 7,left side bar). Although some attenuation of VS-induced ERP shorteningwas also noted in control dogs receiving GαR minigene, the effect wassignificantly less than in subjects receiving Gα1/2 minigene (SEE FIG.6, right side bar). VS-induced AF inducibility was not significantlyaffected in subjects receiving GαR minigene (SEE FIG. 8).

Experiments performed during development of embodiments, of the presentinvention demonstrate the feasibility of a gene-based approach inaltering AF substrate.

What is claimed is:
 1. A method of treating atrial fibrillation in asubject and monitoring the effectiveness of treatment comprising: (a)inserting a device into the subject, the device comprising: (i) anelongate member with a proximal end, a distal tip, and an inner lumen,(ii) an energy-delivery element located at the distal tip of theelongate member, comprising first and second electrodes, and (iii) anelectrophysiology monitoring element; (b) positioning the distal tip ofthe elongate member at a treatment site on an epicardial or endocardialsurface; (c) delivering a nucleic acid gene therapy agent to thetreatment site through the inner lumen of the elongate member; (d)electroporating the treatment site with the first and second electrodes;and (e) recording intracardiac electrophysiologic activity with theelectrophysiology monitoring element after delivering the nucleic acidgene therapy agent to the treatment site.
 2. The method of claim 1,further comprising a step of recording intracardiac electrophysiologicactivity before delivering the nucleic acid gene therapy agent to thetreatment site.
 3. The method of claim 2, further comprising a step ofcomparing the intracardiac electrophysiologic activity before deliveringthe nucleic acid gene therapy agent to the treatment site with theintracardiac electrophysiologic activity after delivering the nucleicacid gene therapy agent to the treatment site.